The present invention relates to a new and distinct variety of citrus rootstock named ‘UFR-15’. The Plant Improvement Team in Lake Alfred, Fla. has pioneered the development and testing of allotetraploid citrus rootstocks. ‘UFR-15’ (identified as “46×20-04-37” in field trials) is a diploid hybrid derived from a conventional cross of Hirado Buntan pink pummelo×Cleopatra mandarin.